[unreadable] [unreadable] The objective of this application is to establish the CORE Leadership Group and a Network Laboratory for the Microbicide Trials Network (MTN). The objective of the Leadership Group is to provide oversight and coordination of a portfolio of clinical trials on topical microbicides for prevention of HIV. The mission of the Microbicide Trials Network is to reduce the sexual transmission of HIV through the development and evaluation of products which reduce the transmission of HIV when applied topically to mucosal surfaces. The goal is to conduct scientifically rigorous and ethically sound clinical trials of microbicide safety and effectiveness which will support licensure of these products. The MTN CORE and Network Laboratory will be headquartered in Pittsburgh under the direction of Dr. Sharon Hillier (CORE) and Dr. Charlene Dezzutti (Network Laboratory). CORE support for the MTN will be coordinated through Pittsburgh in collaboration with investigators at the University of Washington in Seattle and UCLA in Los Angeles, as well as Family Health International, in Raleigh North Carolina. The Network Laboratory is composed of a Comparative Assessment Core, a Site Support and Diagnostic Testing Core, a Virology Gore, a Pharmacology Core, and a Immunology Core. The MTN proposes a portfolio of 15 new clinical trials which span early safety to effectiveness studies. In addition, the MTN will assume direction for two ongoing microbicide studies which were developed under the HPTN, HPTN 035 and 059. Clinical trial sites will be located in the US and in Africa. The MTN will collaborate with other DAIDS sponsored networks and groups engaged in microbicide research internationally. [unreadable] [unreadable] [unreadable]